Apparatus for coating a scoreline in a board



y 30, 1967 J. L. STOKES ETAL 3,322,096

APPARATUS FOR COATING A SCORELINE IN A BOARD Filed June 4, 1964 FIG. 2

2 Sheets-Sheet l May 30, 1967 J. STOKES ETAL 3,322,096

APPARATUS FOR COATING A SCOREIJINE TN A BOARD Filed June 1964 2 Sheets-Sheet United States Patent 3,322,096 APPARATUS FOR COATING A SCORELINE IN A BOARD Joseph L. Stokes and George Attle, Sault Ste. Marie, Ontario, Canada, assignors to Abitibi Power & Paper Company, Limited, Sault Ste. Marie, Ontario, Canada Filed June 4, 1964, Ser. No. 372,466 Claims priority, application Canada, Apr. 3, 1964, 899,490, Patent 740,806 13 Claims. (Cl. 118-105) This invention relates to an apparatus for coating a scoreline in a board such as a plywood panel, a hardboard panel, particle board panels and other sheet materials used in building construction and other architectural furnishings.

For many years flat building board panels have been scored in straight lines to produce decorative relief such as a plank effect as in wall panelling or rectangular as in ceiling tile. The previously available methods of painting these scores have left much to be desired.

Atomizing spray nozzles have been used in two ways with limited success. Small guns have been developed in an attempt to spray a very narrow band into the groove or score line but control of the spray is almost impossible without some overspray. The alternative method is to deliberately overspray and remove the overspray on the surface of the board by either wiping the surface or sanding the whole board surface, (e.g., in plywoo'dto a depth of .006 to .010 inch). In many cases this cannot be done because of printed patterns on the surface.

Another method which is being used to employ pattern P inting or painting wheels to actually ride in the groove and thus transfer a band of colourant. The wheel is contoured to a shape somewhat similar to the cross section of the score line. In production the score lines often vary in depth, width, porosity and surface smoothness which causes uneven paint density and a ragged stripe edge which detracts from the appearance of the finished board.

The object of this invention is to provide .an apparatus for coating scorelines which is superior to those previously used.

In accordance with this invention an apparatus is provided for coating a scoreline in a board comprising means for depositing a liquid coating material such as paint or ink in the scoreline. A spreader extends into the scoreline and is adapted to spread the liquid coating material to cover the surface of the scoreline. It is particularly advantageous for this spreader to be an elongated flexible member and advantages are obtained by suspending such elongated flexible member at each end. The best form for such elongated flexible member is a chain comprising a series of spherical beads which are spaced to provide reservoirs of coating material. The coating material is best deposited on to the bottom of the scoreline by directing a jet of such coating material into the bottom of the scoreline. Relative movement is provided between the board and the spreader so that the spreader travels along the scoreline and spreads the liquid coating material. This relative movement is preferably provided by moving the board while retaining the spreader in a fixed location.

In the drawings which illustrate the preferred embodiments of this invention:

FIGURE 1 is a plan elevation view partly in section illustrating diagrammatically the use of this invention to apply paint to a scoreline in a board;

FIGURE 2 is a sectional elevation View on the line 2-2 of FIGURE 1;

Patented May 30, 1967 FIGURE 3 is a sectional elevation view illustrating another embodiment of this invention;

FIGURE 4 is a sectional elevation view illustrating a modification of this invention.

Referring now to FIGURES 1 and 2 of the drawings, a tank 10 contains a supply of paint which is delivered to paint gun 11 through tube 12. Tube 12 has a shut-off valve 13, paint gun 11 includes a nozzle 14 which is preferably mounted approximately inch above the board surface directly over the scoreline to be painted and is adjusted to deliver a fixed amount of paint into the bottom of the scoreline. The amount required will depend upon a variety of factors such as the score line profile, speed of the panel moving under the nozzle, viscosity of the paint and paint gun orifice size. Successful trials have been made with a viscosity of 38 second #2 Zahn cup, at a board speed of 60 f.p.m. By controlling the speed of the board for other fixed conditions one is able to vary the height to which the sides of the scoreline may be painted. The board is designated by the numeral 15 and is moved by a suitable conveyor 16 in the direction shown by arrow 17. Board 15 has a scoreline 18, such scoreline has a surface provided by base 19 and sloping sides 20 and 21.

An elongated flexible spreader is provided by paint spreader chain 22 which includes spherical beads 23 which are spaced as indicated at 24, and which may be similar to the pull chains used with certain electrical fixtures. Paint spreader chain 22 is mounted at one end on hook 25 which is in turn mounted on spray gun 11. The other end of spreader chain 22 is mounted on hook 26. It will be noted from FIGURE 1 that hooks 25 and 26 are arranged so that a portion of the chain indicated at 27 rides within scoreline 18. It is best to secure one end of the chain by hook 25 as close to the nozzle 14 of the paint gun as possible and as indicated above, it is best to secure the other end of the chain to a fixed member such as hook 26. It is possible to secure the chain only at one end by means of book 25, leaving the other end of the chain floating freely in the scoreline. However, experience has shown that securing both ends of the chain provides a more reliable operation. With one end free, the chain would normally hang vertically when no panels were passing under the nozzle and chain and as the leading edge of each panel came in contact with the chain there is a tendency to catch the chain between spheres causing a jerking and vibration of the chain which can even cause it to bounce out of the scoreline.

The preferred length of the chain 22 is about three inches in length and the diameter of the spherical beads making up the chain should be suitable having regard to the dimensions of the scoreline. As is best shown in FIG- URE 2 the base 19 and sides 20 and 21 of the scoreline should be substantially tangential to the spherical beads 22. By way of example, a scoreline with a included angle between side walls inch deep has been successfully painted with a chain of .125 inch diameter spheres at speeds up to 90 ft./min. Another example would be a scoreline, .062 inch deep, .062 inch wide at bottom of groove and .125 inch wide at surface of panel; this was painted using beads or spheres .093 inch diameter at speeds up to 133 ft./min. For best results the angle between the surface of the board panel and the side wall of the scoreline should be sharp, as opposed to a radius as this permits the meniscus of the paint film to shear along the edge producing a sharp distinct edge to the scoreline paint film.

The distance between successive spheres of the chain which may vary from ,5 inch to ,4; inch depending upon the sphere diameter, acts as a reservoir to store a small 3 quantity of paint which is then available should a variation in scoreline occur or a porous area in the scoreline surface present itself to the chain.

Not only in this type of chain ideally suited to this application in providing a reservoir for paint but being flexible, can accommodate slight variations in the scoreline contour and direction. Upon close examination of the spheres of the chain it is noted that many of the spheres of the chain revolve upon their axes thereby providing a wiping action between the spheres and the walls of the scoreline to clean the spheres and work the paint onto the surface of the scorelines.

Other spreading members could be used in place of the spherical beads such as flexible woven metal cable and helical springs provided the preferred dimensional relationship to scoreline contour is maintained. Generally spherically shaped heads but having four flat sides have also been successively used to fulfil this function. Furthermore, where beads are used, circular beads which are capsule shaped rather than spherically shaped can be used or a combination of spherical and capsule shaped beads could be used.

FIGURE 2 illustrates a modification of this invention to enable the bevelled edges of panels to be painted. These bevelled edges when secured side by side on for instance, a wall or ceiling, form a groove or scoreline between panels. This bevel must be painted or striped to conform with the intermediate scorelines formed in the panels. In FIGURE 3 there is illustrated a board 30 having a "bevelled edge 31, a metal guide fence 32 includes a flange 33 to support board 30 and an inclined face 34 which together with bevel 31 gives a V-shaped scoreline.

' As an alternative the scoreline could be V-shaped and could have sides which are concave or convex. Compression spring 35 which abuts against a fixed abutment 36 urges fence 32 in the direction of board 30 and permits slight variations in the width of the boards. A stand 37 is mounted on fence 32 and has an arm 38 which supports a paint gun 39 having a nozzle 40. A suitable supply of paint (not shown) is provided as in the apparatus shown in FIGURE 1. A paint spreader chain 41 similar to that shown in FIGURE 1 coats the bevel of the board.

The half scoreline or bevel of the metal fence restrains the lateral position of the chain to hold the chains against the bevel of the board or panel to be striped. The paint jet is directed to the bottom of the groove formed by the fence bevel and the bevel of the board or panel. The spheres or other spreading members pick this paint up and coat the bevel of the board. The panels passing between the fences continually wipe the fences thereby preventing a build-up of paint on them.

The apparatus shown in FIGURES 1 and 2 enable similar paint spreading members to be used for painting both complete and half scorelines.

In accordance with the method of this invention the nature of the coating material, the dimensions of the spreader and the speed at which the spreader travels the scoreline are related to the width, depth and side wall angle of the scoreline so that the coating material covers substantially the entire surface of the scoreline without covering more than the surface of the scoreline.

The modification illustrated in FIGURE 4 is desirable under some circumstances to prevent the beads lifting from the scoreline. In the case of some plywood and particle board cores small scorelines are used and the beads are correspondingly small and may for example be A inch in diameter. Where these small beads are used combined with some roughness of texture in the scoreline the beads may lift from the surface of the scoreline with the consequence that some misses in painting the scoreline occur. It has been found that by exerting pressure on a few of the beads as illustrated in FIGURE 4 the scoreline can successfully be coated. In FIGURE 4 a metering gun 50 for coating material has a nozzle 51 at its free end a head 61 having an aperture 62. A holddown shoe for the chain is provided by post 63 which is free to slide in aperture 62 to conform with'variations in the position of the chain. A collar 64 is secured to post 63 by screw 65 to provide an adjustable stop whichbears against head 61 to limit the vertical downward travel of post 63 when no boards are being treated. The hold-down shoe provided by post 63 bears on beads 54a and 54b to prevent them lifting from scoreline 66 in board 67. Typically the hold-down shoe might weigh 4 to 6 ounces and if desired additional weight can be provided above collar 64. a

We claim:

1. Apparatus for coating a scoreline in a board comprising means for depositing liquid coating material in said scoreline, an elongated flexible spreader suspended at each end and having a central portion extending into the scoreline and being adapted to spread the liquid coating material to cover the surface of the scoreline at least such central portion comprising a series of circular beads and means for moving the board relative to said spreader so that the spreader travels along the scoreline and spreads said liquid coating material.

V 2. 'An apparatus as in claim 1, in which the circular beads are substantially tangential to the sides and base provide a reservoir of coating material between the spher- V ical heads.

6. An apparatus as in claim 1 in which the means for depositing a liquid material in the scoreline directs a jet of such coating material into the bottom of the scoreline.

7. An apparatus for coating the bevelled edge of a board comprising means abutting said edge and having a bevelled surface forming a trough in combination with said bevelled edge, means for depositing liquid coating material in said trough, a spreader extending into said trough and being adapted to spread the liquid coating material to cover the surface of the trough and means for moving the board relative to said spreader so that the spreader travels along the bevelled edge of the board and spreads said liquid coating material. 7

8. An apparatus as in claim 7 in which the trough is V-shaped.

9. An apparatus as in claim 7 in which the spreader is a flexible chain comprising a series of spherical beads, such chain being suspended at each end and having a central portion extending into the trough.

10. An apparatus as in claim 7 comprising spring means urging said means abutting the edge in the direction of said board to accommodate variations in the width of said board.

-11. An apparatus for coating a scoreline in a board comprising means for depositing liquid coating material in said scoreline, an elongated flexible spreader suspended at each end and having a central portion extending into the scoreline and 'being adapted to spread the liquid 7 coating material to cover the surfce of the scoreline and V a pressure shoe engaging the elongated flexible spreader to hold it in the scoreline and means for moving the board relative to said spreader so that the spreader moves along the scoreline and spreads said liquid coating mate rial,

5 6 12. An apparatus as in claim 11 in which the pressure References Cited shoe is mounted so as to have freedom of vertical move- UNITED STATES PATENTS ment While the board is being moved relative to the 3,137,436 6/1964 Moors e a1 229 48 spreader.

13. An apparatus as in claim 11 in which the elongated 5 p flexible spreader is a chain comprising a series of cir- ALFRED LEAVITT Primary Examl'le" cular beads and in which the pressure shoe bears on a A. GRIMALDI, Assistant Examiner. few of such beads. 

1. APPARATUS FOR COATING A SCORELINE IN A BOARD COMPRISING MEANS FOR DEPOSITING LIQUID COATING MATERIAL IN SAID SCORELINE, AN ELONGATED FLEXIBLE SPREADER SUSPENDED AT EACH END AND HAVING A CENTRAL PORTION EXTENDING INTO THE SCORELINE AND BEING ADAPTED TO SPREAD THE LIQUID COATING MATERIAL TO COVER THE SURFACE OF HTE SCORELINE AT LEAST SUCH CENTRAL PORTION COMPRISING A SERIES OF CIRCULAR BEADS AND MEANS FOR MOVING THE BOARD RELATIVE TO SAID SPREADER SO THAT THE SPREADER TRAVELS ALONG THE SCORELINE AND SPREADS SAID LIQUID COATING MATERIAL. 